7/30/2019 13 Procedure for Joint Numbering
2/3
LARSEN & TOUBRO LIMITEDPAGE NO.- 2 of 3
DATE:-05.11.07
MSQ UP GRADATION (EPCC 1)
PROJECT REV.NO.- 0
PROCEDURE FOR JOINT NUMBERINGPROCEDURE NO.-
LT/MSQ/P/JN/013
1.0 SCOPE
This procedure outlines the method of joint numbering on the
isometric drawings.
This procedure is applicable forMSQ Unit .
2.0 PROCEDURE:
After receipt of approved drawing, detailed fabrication &
erection scope will be
worked out by planning/ piping engineer based on availability of
drawing and
material. The approved Isometric Drg. Shall be marked with all
the weld joints(shop/field) prior to fabrication in the flow
direction with a number to identify
each weld in the following sequence and one set of this marked
Isometric drawing
shall be submitted to L&T QC & Jacobs for their
reference.
2.1 U/G PIPING
2.1.1 Joint Numbering will be marked after receiving of all
sheets of individual lines. Butt
joints will be marked as a continuation no. J1, J2, J3Jn. Shop
joint read as 1,2,3,
. & field joint will have the prefix FJ i.e. FJ1, FJ2, FJ3,
FJ4
2.1.2 Branch joints will be marked as a continuation number from
BR J1, J2, J3Jn.
2.1.3 Socket joints will be marked as a continuation number SW
J1, J2, J3Jn.
2.1.4 Miter joints will have prefix MJ.
2.1.5 Re welded joints will have suffix RW to the previous joint
number. For example joint
number 1 is re welded then it will be marked as 1RW.
2.1.6 Cut out joints in Radiography will have suffix N to the
previous joint number.
2.1.7 Repair joints in radiography will have suffix R1, R2to the
previous joint number
2.1.8 Penalty joints in radiography will have suffix P1, P2to
the previous radiography
number.
2.1.9 Modification joints will have suffix M to the previous
joints.
2.1.10 Additional joints will have suffix A, B, Cfor example an
additional joint is coming in
between joint number 2 & 3, then this additional joint
number will be marked as 2A.
APPROVED BY L & T REVIEWED / APPROVED BY JACOBS
7/30/2019 13 Procedure for Joint Numbering
3/3
LARSEN & TOUBRO LIMITEDPAGE NO.- 3 of 3
DATE:-05.11.07
MSQ UP GRADATION (EPCC 1)
PROJECT REV.NO.- 0
PROCEDURE FOR JOINT NUMBERINGPROCEDURE NO.-
LT/MSQ/P/JN/013
2.1.11 This Numbering will be maintained in a welding control
database package i.e. ALPS
2.2 A/G PIPING:
2.2.1 Joint Numbering will be marked after receiving of all
sheets of individual lines. Butt
joints will be marked as a continuation no. J1, J2, J3Jn. Shop
joint read as 1,2,3,
. & field joint will have the prefix FJ i.e. FJ1, FJ2, FJ3,
FJ4
2.2.2 Branch joints will be marked as a continuation number from
BR J1, J2, J3Jn.
2.2.3 Socket joints will be marked as a continuation number SW
J1, J2, J3Jn.2.2.4 Miter joints will have prefix MJ.
2.2.5 Re welded joints will have suffix RW to the previous joint
number. For example joint
number 1 is re welded then it will be marked as 1RW.
2.2.6 Cut out joints in Radiography will have suffix N to the
previous joint number.
2.2.7 Repair joints in radiography will have suffix R1, R2to the
previous joint number.
2.2.8 Penalty joints in radiography will have suffix P1, P2to
the previous radiography
number.
2.2.9 Modification joints will have suffix M to the previous
joints.
2.2.10 Additional joints will have suffix A, B, Cfor example an
additional joint is coming in
between joint number 2 & 3, then this additional joint
number will be marked as 2A.
2.2.12 This Numbering will be maintained in a welding control
database package i.e. ALPS
Note: No joint number will be repeated in the same line
number.
APPROVED BY L & T REVIEWED / APPROVED BY JACOBS
